Mayor Colette Roy-Laroche said her council had to make a hard choice when it decided to continue to allow trains to run through Lac-Megantic, which one year ago this weekend was devastated by a derailment that killed 47 people.

"The municipal council juggled between reason and emotion but chose the survival of the local and regional community," Roy-Laroche told a news conference on the eve of ceremonies marking the one-year anniversary of the July 6, 2013, tragedy.

Lac-Megantic, which was built around the railroad, grabbed worldwide attention when a train loaded with volatile fuel oil careened off its tracks as it barrelled through town and exploded.

A large section of the town was destroyed in a series of explosions and fireballs that were picked up in satellite images from space.

While the tragedy is still keenly felt in the community of about 6,000, Roy-Laroche said she feels the weekend's events are important to help people move forward.

Lac-Mégantic Mayor Colette Roy-Laroche says the loss of 47 people killed in last year's explosion left a deep mark on the community. (CBC)

"The commemoration events . . . are an important step, an important step to make peace with this tragedy, to also find our serenity," she said Friday. "There will be difficult moments, I know, but also moments where we come together as a community."

Included in the events will be the planting of flowers by Roy-Laroche and a group of local children as well as the release of a flock of butterflies.

A number of musical and social events will also be held.

A midnight mass followed by the vigil will complete Saturday's activities.

On Sunday, dignitaries including Quebec Premier Philippe Couillard will join families and Lac-Megantic residents for a commemorative mass followed by the dedication of a monument and a procession.

Rev. Steve Lemay, the parish priest, said the Ste-Agnes Church and its statue of Jesus had become icons of determination in the community. A photo of the statue, its arms outstretched amid the fireballs of the July 6 explosions, had circulated around the world when the tragedy happened.

"Because of its location, the church became a powerful symbol of resilience," Lemay told a news conference. "It stood up before the tragedy and it is for us an an example of people living through this ordeal, of standing up in front of the difficulties."

The day will wrap up with a concert.

Many people say they will skip the events as they continue to cope with the trauma.

The clinical co-ordinator for psychosocial assistance in the region has said her team treated 423 people in the Lac-Megantic area during the last 10 months.

Those interventions included 188 group and 2,035 individual therapy sessions.

Among the complaints were anxiety, flashbacks and a "terrible fear" of the area's train tracks.

The federal government pledged to pull all old tank cars, known as DOT-111s, off Canada's rails during the next few years. The pledge involves removing up to 5,000 of the rupture-prone tankers from the tracks within a month.

The Transportation Safety Board also recommended that dangerous goods should not be left unattended on a main track and also that rail equipment be properly secured.

The Railway Association of Canada, a group that represents rail companies, says the industry is committed to do what is required in the areas of safety, training and emergency preparedness to prevent another disaster like the one that occurred in Lac Megantic.

It says the rail industry in North America is spending $2.5 billion this year to ensure the safety of its infrastructure.

The town is slowly rebuilding, although business people have said that government cash is slow in coming.

The federal and provincial government had pledged millions of dollars each to help in the recovery effort.

Montreal, Maine and Atlantic Railway, which had filed for bankruptcy protection, was sold in a closed-door auction in January for $15.85 million. The buyer was later revealed to be Railroad Acquisition Holdings, an affiliate of New York-based Fortress Investment Group.

Clarifications

On account of a technical error, an outdated story about Lac-Mégantic from May 8, 2014, was erroneously published in this space with a July 4, 2014, time stamp.